Owning a business is a satisfying and potentially lucrative occupation. The key to being successful in business is to know yourself. Use strengths and employ others to fill weaknesses. The focus should always be on customer demand and satisfaction. As for investing, know your goals and aim for them. Use your proceeds any time you want.

Today's column is the response to the letter from three young entrepreneurs presented in yesterday's column.

Dear Ian, Hannah, and Jacob,

I want to begin by saying that you three are remarkable. When you ask whether my brother and I as children were like you, I can only say that I wish we'd had your sense of cooperative enterprise. The truth is that my brother and I only really began to cooperate in our mid-20s, when (not coincidentally?) we entered business together. (And you're right -- it is really neat to be in business with your brother.) We had lots of fun playing games growing up, but I wasn't as good as Ian at being a leader. And as for enterprise, Tom and I spent more time making crank calls to radio shows than crafting things that other people might actually appreciate and purchase. We had lots of fun too, but yours is more productive.

You say you've wanted to make money for a long time. Great, because money is opportunity, and by earning it, saving it, and growing it, you will be able to do anything you want to in life, and be lucky and privileged enough to be able to pass on some of that opportunity to others. There are two excellent ways to make money in this world. The first is by starting your own business; the second is by investing in the businesses of others. Between the two, I should say that starting your own business is the more satisfying and lucrative. I love investing very much, and Tom and I feel very privileged to be teaching so many people better ways of doing that. These things said, my advice to you wouldn't be true if I didn't point out that the people who make the most money in this world usually start businesses. As much as people talk about Warren Buffett as a great investor (you may remember us mentioning the billionaire on our PBS show), the fact is that he runs his own company, and that's where so much of his wealth was built and is centered. He's a great businessman, an excellent thing to be.

From your letter, it's obvious to me that you also possess a very fine entrepreneurial instinct, one that is well beyond your years. That's a great sign for your future. You will each have your own interests, and strengths and weaknesses. That's why I feel it's really important in the next decade of your life to get to know yourselves as best you can. Accentuate and develop your strengths and don't hide or excuse your weaknesses -- acknowledge them and engage others in helping you compensate. Speaking only for myself, I think I'm good at coming up with new ideas and starting businesses, but not necessarily very good at running them. For instance, in May of last year we hired our first CEO (chief executive officer) to run our business here at The Motley Fool; we think he can do a better job than we would.

You've already learned two important lessons from your own business efforts. The first is the importance of making stuff that other people like. Capitalism works because it forces businesses to cater their products and services to what people actuallywant, as opposed to what someone (a poor businessman, a socialist government, etc.) incorrectly thought they wanted. Selling Nutcrackers at a Christmas fair is a perfect example. The second thing you've learned is that your efforts will be set back from time to time by external forces outside of your control. What must you or your business do, when this happens? Adapt. It is the ability to adapt which separates good businesses from bad ones, strong people from weak ones, and ultimately, surviving species from doomed ones. So when the Belgian flag throwers don't show up, by all means, call your figures something else! Great story.

I have focused on your entrepreneurial efforts, but you've also asked some great investment questions. The short answers to your questions are that YES you can begin investing now. I wish every early teen recognized that and was asking the great questions you are asking. We have devoted an online area to getting started investing as a child, so please check out www.fool.com/teens -- and in particular, our articles "How to Grow a Million Dollars" and "Why Invest?" You have taken to heart our message of "invest in things you know and love." If you have ANY additional questions about money and investing, you can use our Teens & Their Money discussion board to get them answered. Just post there. Also, here are some good books for beginning investing in your younger years.

When can you use the money you make because you invested? When you want to! That's why we invest -- we invest to grow our money up to the point that we can then use it for the original purpose we invested. If you just leave it there and never do anything with it, it is in many ways a sad waste. (Though far sadder are those who never invested at all, or who went through life unable to pull themselves out of debt.) Please note that many of us invest for our futures, and for those of our children or grandchildren. So while maybe we don't have an exact date or purpose for our savings, and we may frequently be tempted to use it for our own present purposes, it is both an intelligent and noble decision to exercise patience and leave that savings in to grow. If you've read our "How to Grow a Million Dollars" article you already know how critical compounding your returns is....

As you know, we have many people in Fooldom who are as well or better qualified to take your questions than I am, and I invited them to write you a response as well. We received nearly 100 submissions, from old and young, from a CEO, from the Netherlands, and from a young man named Pedro who reminds you that you can charge higher prices as a young retailer because adults think it's cute and want to support you! Many were written by adults wishing they'd been asking the very questions you're asking when they were twelve. I'm sending you all of these responses -- they're quite amazing, each written with affection and your best interests at heart.

I wish to close by saying your mother has a great head on her shoulders. Listen to her.

Very Foolishly,

David Gardner, April 12, 2001

Note to regular Rule Breaker readers: Starting next week, we will run three Rule Breaker articles per week. They will appear on Monday, Wednesday, and Friday. For a full explanation for the change, see our letter to the community.

NoteThe Fool Portfolio was launched on August 5, 1994, with $50,000. It was renamed the Rule Breaker
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has evolved with time and experience. In July 2001, the portfolio began adding $12,500 each quarter (We
missed Jan. 2002, so we added $25,000 in April 2002). We skip a quarter if we have enough uninvested
cash or cash available in stocks we would prefer to sell to make new investments. All transactions are
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